Rio Ferdinand will leave Manchester United after 12 years at Old Trafford as the former Premier League champions will start a new era without their two senior central defenders.
The former England captain, who will be 36 in November, claimed he made the decision to seek a new challenge elsewhere, although there are reports United had decided not to offer him a new contract.
Ferdinand, who lost his place under David Moyes and only started nine league games under the Scot, made his 455th and last United appearance in Sunday's 1-1 draw at Southampton.
He said in a statement: "I have thought long and hard over the last few months about my future and, after 12 fantastic years playing for what I regard as the best club in the world, I have decided the time is right for me to move on."
United captain Nemanja Vidic had already announced his departure and has agreed to move to Inter Milan. Ferdinand cost United a British record fee of 30 million pounds when he arrived from Leeds in 2002 and went on to win six Premier League titles. He formed a fine partnership with Vidic after the Serb joined in 2006 and they were the cornerstones of a defence that helped them win the Champions League in 2008 and only conceded 24 goals in the 2008-09 league season.
Ferdinand added: "I joined Manchester United in the hope of winning trophies, and never in my wildest dreams could I have imagined how successful we would be during my time here. There have been so many highlights, playing alongside some great players who have become good friends, winning my first Premier League title and also that fantastic night in Moscow are memories that I will cherish forever.
"Circumstances didn't allow for me to say goodbye the way I would have liked but I'd like to take this opportunity to thank my team-mates, staff, the club and the fans for an unbelievable 12 years that I'll never forget. Winning trophies I dreamed about as a kid came true at this great club.
Ferdinand's exit leaves United with three centre-backs from a younger generation -- Jonny Evans, Chris Smalling and Phil Jones -- and could mean their next manager has to sign a replacement.
United could lose a third experienced defender, with left-back Patrice Evra also out of contract in the summer. Ferdinand, who will be a television pundit in this summer's World Cup, has reportedly attracted interest from clubs in Turkey and the United States.
He said: "I am feeling fit and healthy, ready for a new challenge and looking forward to whatever the future holds for me."